Thrust bearing arrangement for a power tool transmission

A reciprocating power saw transmission comprising:

• a housing;
• a saw blade carrier having at least an internal portion located within the housing for supporting a saw blade outside the housing;
• guide means for guiding the saw blade carrier in generally linear reciprocating movement along an axis of reciprocation including a cover plate extending at least partially within the housing and providing at least part of the guidance for the saw blade carrier;
• reciprocating motion means located within the housing and including a speed reducing bevel gear set, including an input pinion and an output crown wheel, said crown wheel being journaled by a radial bearing and rotating in a plane parallel to and adjacent to the saw blade carrier, and having a back face and carrying an eccentrically mounted drive element for engaging and generating reciprocating motion in the saw blade carrier;
• and
• thrust bearing means effective between the crown wheel and the carrier so that in operation under load, when the input pinion is imposing an axial loading on the crown wheel, the axial loading is received by the saw blade carrier.

A reciprocating power saw transmission comprising:

• a housing;
• an elongated saw blade carrier having at least one generally planar side, at least an internal portion of the carrier being located within the housing for supporting a saw blade outside the housing;
• guide means for guiding the saw blade carrier in generally linear reciprocating movement along an axis of reciprocation in a plane parallel to the at least one generally planar side;
• an extensive surface within the housing defining a plane parallel to the plane of reciprocation and associated with the guiding of the saw blade carrier;
• reciprocating motion means located within the housing and including a speed reducing bevel gear set, including an input pinion and an output crown wheel, said crown wheel being journaled by a radial bearing and rotating in a plane parallel to and adjacent to the extensive surface and carrying an eccentrically mounted drive element for engaging and generating reciprocating motion in the saw blade carrier;
• and
• thrust bearing means effective between a portion of the crown wheel adjacent its circumferential periphery and the extensive surface so that in operation under load, when the input pinion is imposing an axial loading on the crown wheel, the axial loading is received by the extensive surface.